Vaccination reduces long-term COVID risk for rheumatism patients

Patients with rheumatological diseases who developed breakthrough COVID-19 infection after vaccination were less likely to suffer from long-term symptoms than unvaccinated but otherwise similar patients, the researchers said.

Among 280 patients with rheumatic diseases (most with some form of autoimmune arthritis or connective tissue disease) who survived acute COVID-19, 21% of those vaccinated against the disease experienced symptoms lasting 90 days or more after the acute phase, compared to 41% of patients in unvaccinated patients, according to Dr. Naomi Patel of Massachusetts General Hospital in Boston and colleagues.

When the data were adjusted for age, gender, race, comorbidities, and use of immunosuppressants, a vaccinated patient was only one-tenth as likely to develop post-acute COVID symptoms, also known as “long COVID,” by day 90 of unvaccinated patients (adjusted OR 0.10, 95% CI 0.04-0.22), the researchers wrote in a preprint manuscript that appears on the medRxiv Side? site.

Rates of post-acute symptoms lasting 28 days were also lower in the vaccinated patients: 41% versus 54% (P=0.04), with an adjusted odds ratio of 0.49 (95% CI 0.29-0.83).

“These results suggest that vaccination is possible in patients with SARDs despite a higher risk of breakthrough infection [systemic autoimmune rheumatic diseases] not only reduces the risk of severe acute consequences, but also long-term consequences,” Patel and colleagues wrote.

However, the group also warned that vaccination is not a panacea for these patients. The occurrence of post-acute symptoms, they wrote, “remains common in SARD patients, even after vaccination, and when present, the severity is similar to that in those who were either unvaccinated or only partially vaccinated.”

The 280 patients in the study were all treated for COVID-19 at Boston’s Mass General Brigham system from March 2020 to July 2022, whose medical records contained billing codes for rheumatic diseases. When contacted after recovering from the acute infection, they agreed to take part in a long-term follow-up study that included questionnaires on various aspects of their health. This study started in March 2021.

Just under 60% of the total group had autoimmune arthritis diagnoses, 24% had autoimmune connective tissue disease, and 9% had some type of vasculitis. These diagnoses were well balanced between the vaccinated (n=116) and unvaccinated (n=164) cohorts.

However, there were some important differences between the groups. More in the vaccinated cohort used disease-modifying anti-rheumatic drugs (DMARDs) such as methotrexate, mycophenolate mofetil, antimalarials, and biologics. Obesity was significantly more common in the unvaccinated patients.

As is usual with systemic autoimmune diseases, 80% of both groups were women. The median age was 52 years and more than 80% were white.

About half of the unvaccinated group had COVID-19 before February 2021, when vaccines first became widely available. Thereafter, most infections occurred in vaccinated patients (100 vs. 14). Only 4% of the vaccinated group required hospitalization compared to 16% of the unvaccinated (hence the authors’ comment on the reduced risk of serious acute sequelae).

All 280 provided follow-up data for the first 28 days after recovery from the acute phase; Data at 90 days and beyond were available for 47 in the vaccinated group and 159 in the unvaccinated group.

Post-acute symptoms included pain, fatigue, and functional difficulties. At the time of completing the questionnaire (up to 204 days after the acute phase), median pain scores on the short-form McGill pain instrument were 4 in the vaccinated group versus 5 in the unvaccinated (P=0.04). The mean scores from the Fatigue Symptom Inventory were 48 in the vaccinated and 55 in the unvaccinated (P=0.08). Mean functional ability scores on the modified health assessment questionnaire were 0.1 for both groups, and self-reported general health status was also similar.

Participants were also asked to record days with and without symptoms, and these differed significantly between groups. Overall, during follow-up, the vaccinated patients rated themselves as symptom-free for an average of 138 days compared to 109 days for the unvaccinated – a difference of almost a month.

Limitations of the study included reliance on participants’ self-reports, differences in predominant circulating virus variants over time and in acute-phase treatments used, and possible mixing of SARD symptoms with those of post-acute COVID. In addition, the report was published as a preprint manuscript and was therefore not peer-reviewed.